Tuning apparatus



y 1959 J. E. MYERS, JR 2,894,225

TUNING APPARATUS Filed Oct. 29. 1956 l l l I I l 1 I I INVENTOR.

JAMES ELMER MYERS,JR.

A, TUNING APPARATUS it James Elmer Myers, Jr., Hammonton, NJ. 1 Application October 29, 1956, Serial No. 618,822

3 Claims. 01. ass-s2 Generally speaking, the present invention relates to the useof tuned lines as parallel and series resonant circuits. More. specifically, to a means of compacting such tuned lines into a small space and making them gradually turnable. over an extremely wide range of frequencies and yet maintaining maximum efliciency (Q) characteristics. n addition, this device provides a means of completely United States Patent- Patented July 7, 1959 switching means connected to and being physically part of the contacts 10 and 11, being normally open unless positively physically held in closed position by meansof the non-conductive block 7. This may. he provided by having said movable portions of the contacts 10 and 11 made of spring-like material so as to always return to the normal open position shown in the drawing upon removal of physical pressure thereto whenever the non-conductive block. 7 is moved toward the right into a. position such as that shown in the drawing. It can be seen that tuned lines 17 and 18 have been inserted in series with lines 12 and 13 in such a manner that the physical lengths of lines 12and 13 are now increased, allowing slider 14 to be tunable to a lower range of frequencies. t

, In the event that it is desired to insert additional tuned resonant 1 circuit sections and to thereby decrease the resonant frequency of the complete tuned circuit, addiremoying" itself entirely from any associated circuit or L:

system when not in actual use. This is extremely important, where employed with extremely short wave lengths, since short leads, switch contacts or terminal some, etcl, in themselves may react as a resonant stub orQIc'ircuit having undesirable or detrimental effect.

i flwidefriequency range is accomplished by providing a methodoffgradually varying the resonant length of a timed "linebyslider actionand in addition, providing a switching; method which causes the extension of the effectional tuned resonant circuit sections similar to those shown at 20 and 21.xnay.be added to the left end of the apparatus shown in theldrawing toany desired .degree. The number of additional tuned resonant circuit sections to be iadded will determine the. necessary physical length of the slider member or block 7, as it must be of a length such as to completely span all of the tuned resonant circuit sections to be: employed whereby all of those which have been passed by the slider contact means 8 and 9 tive length of the legs ofa tuned line in unlimited con- W secutive steps, each successive step expanding the tunablerange of the resonant line in the direction of lower ne'queneies, i i p The singlefigure of the drawing is a perspective diagranmiatic view illustrating one exemplary embodiment of the invention. q r

The single figure of the drawing shows this new switching methodinits inoperative or Ofi."po'sition. By

connecting terminals land 2 to the antenna terminals of s'ioh lirie to an antenna system,- it can be seen that electrical connection between pointsland 3 is accomplished through conductor 5, and points 2 and 4 completed through conductor 6, thus completing the normal transmission line circuit from the television receiver to the antenna. The switching system in the position as shown has completely removed the device from having any effect on the transmission line circuit on any frequency.

By moving slider block 7, in the direction of the arrow towards the switching contacts to the first position of operation where sliders 8 and 9 make connection with contacts 10 and 11, it can be seen that the resonant line composed of legs 12 and 13 are now connected directly to the antenna transmission line through the switch.

Slider 14, shown connected across legs 12 and 13 is used to tune the resonant line to the desired frequency. It can be seen that the minimum wavelength tunable occurs when the slider is moved to the position nearest the switching device and is limited by the minimum physical dimensions of the switch. The maximum wavelength tunable in this position is reached when the slider 14 is moved to the extreme ends of the lines.

By moving the sliding block 7, further towards the switching contacts, we reach the second position of operation, which is at the point where the contacts 8 and 9 now make contact with points 15 and 16. In this position of operation the non-conductive block 7 which supports sliders 8 and 9, has physically pressed switched contacts 10 and 11 closed; the movable portions of the will be held in closed position by the body portion of the slider block 7 while the slider contact means 8 and 9 will effectively connect. the elements 5 and 6 to the serially last-end of the serially last of the tuned resonant circuit sections which has been serially electrically interconnected by closure of corresponding ones of the switchingmeans, such as those shown at 10 and 11.

Moving of the tuning block to each successive position of operation continues to. physically lengthen legs 12 and 13 resultingin the ability to tune over consecutively lower frequency ranges. a y

Each section tobe inserted is so selected that, with slider 14 adjustedlto its highest frequency position, the tunable frequency overlaps the lowest frequency tunable r a by s1ider'14 on the previous tuning range. This provides a television receiver and terminals 3 and 4 to a transmiscontinuous tuning from maximum to minimum. frequencies without allowing any untunable frequencies Within this. range to exist. Additional positions may be added to the switching arrangement as illustrated until the lowest possible frequency range desired to be tuned is reached.

Telescoping slider 19, is shown as an alternate method of varying the resonant frequency of the tuned line instead of using a slider, 14. The choice between slider 14 and 19 determines whether the unit shall act as a series or parallel resonant circuit in its various applications.

The use of this switching arrangement is foreseen in other applications other than described above. Its use is foreseen as a device connected in series with a transmission line to make the transmission line length adjustable so that better impedance matching and efiiciency can be accomplished.

The described switching arrangement as set forth may be used whenever very compact and highly sensitive frequency measuring or controlling devices are required. Since tuned lines are in effect resonant. circuits, other componets which may be used to form tuned circuits may be substituted for the tuned lines in actual application. The appended claims are therefore intended to cover any modifications coming within the true spirit and scope of the invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. Apparatus for controllably varying the resonant length of a tuned circuit, comprising: a plurality of tuned circuit sections arranged in electrically serially .3 adjacent relationship; normally open switching means serially interconnected between the serially adjacent tuned circuit sections and positioned along a path of travel; and 'a switchingmeans-closing member mounted for switching-means-closing movement along said path of 'travel in a first direction into abutting switching-meansclosing contact with saidswitching means for closing and maintaining said switching means in closed relationship, and .for switching-means-opening movement along said path of travel in a second direction opposite to said first direction outof abutting switching-means-closingcontact with said switching means for returning said switching means tonormalopen relationship, :said switching-means closing member being provided with electrical contact meansadapted to be electrically connected to applied circuitry which is to be effectively tuned and also electrically connected to the serially last of the tuned circuit sections which have been serially electrically interconnected by-corresponding closure of said switching means. 1 12.,Apparatus for controllably varying the resonant length of a tuned circuit, comprising: a plurality of tuned circuit sections arranged in electrically serially ad- 3. Apparatus for controllably varying the resonant length of a tuned circuit, comprising: a plurality of tuned circuit sections arranged inelectrically serially adjacent relationship and physically serially adjacent relationship, each of said tuned circuit sections comprising a pair of parallel conductors, the serially first one of said tuned circuit sections being provided with slidable tuning means for varying the tuning thereof; switching means including a plurality of fixed switch contacts positioned along a linear path of travel and connected to serially adjacent ends of the plurality of tuned circuit sections and to the serially last end of the serially last one of the tuned circuit sections, and normally resiliently open movable switch contacts mounted for closing movement to serially interconnect said fixed switch contacts and the serially adjacent plurality of tuned circuit sections connected thereto; a switching-means-closing slider member of electrical insulating material; and longitudinal channel means jacent. relationship, each of .said tuned circuit sections comprising 'a pair of parallel conductors, the serially first one of said tuned circuit sections being provided with slidable tuning means for varying the tuning thereof; normally resiliently open switching means serially interconnected between the serially adjacent tuned circuit sections andpositioned along a linear path of travel; and a 'switching-means-closing slider member of electrical insulating .material mounted for slidable switching-meansclosing movement along said path of travel in a first direction from the serially first one of said tuned circuit sections toward the serially last one of said tuned circuit sections into abutting switching-means-closing contact with said switching means for closing and maintaining saidswitching means in closed relationship, and for oppositely directed 'slidable switching-means-opening movementalong said path of travel out of abutting switchingmeans-closing contact with said switching means for resiliently returning said switching means to normal open relationship, said switching-means-closing member being provided with electrical contact means adapted to be electrically connected to applied circuitry which is to be eflectively tuned and also electrically connected to theserially last end of the serially last of the tuned circuit sections which have been serially electrically interconnected by corresponding closure of said switching means.

slidably mounting said switching-means-closing' slider member for slidable switching-means-closing movement along said path of 'travel in a first direction from the serially first one of said tuned circuit'sections toward the serially last one of said tuned circuit sections into abutting switching-means-closing contact with said switching means for closing and maintaining said switching means in closed relationship, and for oppositely directed slidable switching-means-opening movement along said path of travel out of abutting switching-means-clo'sing contact with said switching means for resiliently returning said switching means to normal open relationship, said switching-means-closing member being provided with electrical contact means adapted to be electrically connected to'applied circuitry which is to be effectively tuned,

and also being slidably movable with said switchingmeans-closing member along said linear path of travel in said first direction into successive electrical contact with the fixed switch contacts and into a position electrically connected to the serially last end of the serially last one of the tuned circuit sections which have been serially interconnected by corresponding closure of said movable switch contacts.

References Cited in the file of this patent UNITED STATES PATENTS 

